Always flush the display FIFO on vsync pulse, even if not explicitly
requested by the panel via MIPI_DSI_MODE_VSYNC_FLUSH mode_flag.
The display FIFO should be empty at vsync. Flushing it at vsync pulses
helps to remove garbage that may have entered the FIFO during startup
(if synchronisation between upstream display controller and Samsung DSIM
is lacking) and that may persist in form of last frame's leftovers on
subsequent frames. Flushing the display FIFO if it is already empty
should have no effect.
This will allow to remove the MIPI_DSI_MODE_VSYNC_FLUSH flag, which is
only used by the Samsung DSIM bridge driver. Arguably this flag doesn't
belong in the panel configuration at all: flushing the display FIFO on
vsync is a workaround for issues with the integration between display
controller and DSI bridge, not a property of the DSI link between bridge
and panel. No panel actually has a requirement to receive garbage or old
frame content after vsync.
I wonder if host controller FIFO resets are mentioned by the MIPI DSI
specification at all. This patch is based on the assumption that the
MIPI_DSI_MODE_VSYNC_FLUSH flag only exists because the DSIM_MFLUSH_VS
bit happens to be located in the same register as the bits controlling
the DSI mode.
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20250627-dsi-vsync-flush-v2-1-4066899a5608@pengutronix.de
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
panthor_gpu_block_power_on() takes a register offset (rdy_reg) for the
purpose of waiting for the power transition to complete. However, a
copy/paste error converting to use the new 64 register functions
switched it to using the pwrtrans_reg register instead. Fix the function
to use the correct register.
Fixes: 4d230aa209 ("drm/panthor: Add 64-bit and poll register accessors")
Signed-off-by: Steven Price <steven.price@arm.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/r/20250630140704.432409-1-steven.price@arm.com
The DSI host has different modes in prepare() and enable() functions,
prepare() is in LP command mode and enable() is in HS video mode.
>From our experience, generally the initialization sequence needs to be
sent in the LP command mode.
Move the setup init function from enable() to prepare() to fix a display
shift on rk3568 evb.
Tested on rk3568/rk3576/rk3588 EVB.
Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20250618091520.691590-1-andyshrk@163.com
Since the drm_mock_scheduler does not have real users in userspace, nor
does it have real hardware or firmware rings, it's not necessary to
signal timedout fences nor free jobs - from a functional standpoint.
Still, the dma_fence framework establishes the hard rule that all fences
must always get signaled.
The unit tests, moreover, should as much as possible represent the
intended usage of the scheduler API.
Furthermore, this later enables simplifying the mock scheduler's
teardown code path.
Make sure timed out hardware fences get signaled with the appropriate
error code.
Signed-off-by: Philipp Stanner <phasta@kernel.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250605134154.191764-2-phasta@kernel.org
The commit d391c58271 ("drivers/firmware: move x86 Generic System
Framebuffers support") moved the sysfb*.c source files from arch/x86
to drivers/firmware, because the logic wasn't x86 specific and could
be used by other architectures.
But the drivers/firmware path is not listed in MAINTAINERS, which led
to the files being orphaned and scripts/get_maintainer.pl not listing
a mailing list to Cc anymore.
Now that we have an entry for all the firmware-provided framebuffer code,
add the missing sysfb files to make sure correct folks and list is Cc'ed.
Fixes: d391c58271 ("drivers/firmware: move x86 Generic System Framebuffers support")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Closes: https://lore.kernel.org/lkml/aF53djlieUNF_-aV@smile.fi.intel.com/
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250627113328.2703491-1-javierm@redhat.com
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Move big-endian support from drm_fb_xrgb8888_to_rgb565() into the new
helper drm_xrgb8888_to_rgb565be(). The functionality is required for
displays with big-endian byte order. Update all callers.
With the change applied, drm_fb_xrgb8888_to_rgb565() has the same
signature as the other conversion functions, which is required for
further updates to drm_fb_blit(). Also makes the format-conversion
helper available to panic handlers, if necessary.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://lore.kernel.org/r/20250625114911.1121301-1-tzimmermann@suse.de
To avoid duplicating the tricky bo locking implementation,
Implement ttm_lru_walk_for_evict() using the guarded bo LRU iteration.
To facilitate this, support ticketlocking from the guarded bo LRU
iteration.
v2:
- Clean up some static function interfaces (Christian König)
- Fix Handling -EALREADY from ticketlocking in the loop by
skipping to the next item. (Intel CI)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20250623155313.4901-4-thomas.hellstrom@linux.intel.com
To the best of my knowledge, all drivers in the mainline kernel adding a
DRM bridge are now converted to using devm_drm_bridge_alloc() for
allocation and initialization. Among others this ensures initialization of
the bridge refcount, allowing dynamic allocation lifetime.
devm_drm_bridge_alloc() is now mandatory for all new bridges. Code using
the old pattern ([devm_]kzalloc + filling the struct fields +
drm_bridge_add) is not allowed anymore.
Any drivers that might have been missed during the conversion, patches in
flight towards mainline and out-of-tre drivers still using the old pattern
will already be caught by a warning looking like:
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 2 PID: 83 at lib/refcount.c:25 refcount_warn_saturate+0x120/0x148
[...]
Call trace:
refcount_warn_saturate+0x120/0x148 (P)
drm_bridge_get.part.0+0x70/0x98 [drm]
drm_bridge_add+0x34/0x108 [drm]
sn65dsi83_probe+0x200/0x480 [ti_sn65dsi83]
[...]
This warning comes from the refcount code and happens because
drm_bridge_add() is increasing the refcount, which is uninitialized and
thus initially zero.
Having a warning and the corresponding stack trace is surely useful, but
the warning text does not clarify the root problem nor how to fix it.
Add a DRM_WARN() just before increasing the refcount, so the log will be
much more readable:
[drm] DRM bridge corrupted or not allocated by devm_drm_bridge_alloc()
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
[...etc...]
A DRM_WARN is used because drm_warn and drm_WARN require a struct
drm_device pointer which is not yet available when adding a bridge.
Do not print the dev_name() in the warning because struct drm_bridge has no
pointer to the struct device. The affected driver should be easy to catch
based on the following stack trace however.
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250620-drm-bridge-alloc-getput-drm-bridge-c-v9-3-ca53372c9a84@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
The AM62x and AM62Px SoCs feature 2 OLDI TXes each, which makes it
possible to connect them in dual-link or cloned single-link OLDI display
modes. The current OLDI support in tidss_dispc.c can only support for
a single OLDI TX, connected to a VP and doesn't really support
configuration of OLDIs in the other modes. The current OLDI support in
tidss_dispc.c also works on the principle that the OLDI output can only
be served by one, and only one, DSS video-port. This isn't the case in
the AM62Px SoC, where there are 2 DSS controllers present that share the
OLDI TXes.
Having their own devicetree and their own bridge entity will help
support the various display modes and sharing possiblilities of the OLDI
hardware.
For all these reasons, add support for the OLDI TXes as DRM bridges.
Signed-off-by: Aradhya Bhatia <a-bhatia1@ti.com>
Signed-off-by: Aradhya Bhatia <aradhya.bhatia@linux.dev>
Tested-by: Michael Walle <mwalle@kernel.org> # on am67a
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://lore.kernel.org/r/20250528122544.817829-5-aradhya.bhatia@linux.dev
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
The dss dt schema and the tidss driver have kept the single-link OLDI in
AM65x integrated with the parent video-port (VP) from DSS (as the OLDI
configuration happens from the source VP only).
To help configure the dual-lvds modes that the OLDI has to offer in
devices AM62x and later, a new OLDI bridge driver will be introduced.
Mark the existing OLDI code separately by renaming all the current OLDI
identifiers with the 'AM65X_' prefix in tidss driver, to help
distinguish from the upcoming OLDI bridge driver.
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Aradhya Bhatia <aradhya.bhatia@linux.dev>
Link: https://lore.kernel.org/r/20250528122544.817829-4-aradhya.bhatia@linux.dev
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
The OLDI transmitters (TXes) do not have registers of their own, and are
dependent on the source video-ports (VPs) from the DSS to provide
configuration data. This hardware doesn't directly sit on the internal
bus of the SoC, but does so via the DSS. Hence, the OLDI TXes are
supposed to be child nodes under the DSS, and not independent devices.
Two of the OLDI TXes can function in tandem to output dual-link OLDI
output, or cloned single-link outputs. In these cases, one OLDI will be
the primary OLDI, and the other one, a companion. The following diagram
represents such a configuration.
+-----+-----+ +-------+
| | | | |
| | VP1 +----+--->+ OLDI0 | (Primary - may need companion)
| | | | | |
| DSS +-----+ | +-------+
| | | |
| | VP2 | | +-------+
| | | | | |
+-----+-----+ +--->+ OLDI1 | (Companion OLDI)
| |
+-------+
The DSS in AM625 SoC has a configuration like the one above. The AM625
DSS VP1 (port@0) can connect and control 2 OLDI TXes, to use them in
dual-link or cloned single-link OLDI modes. It is only the VP1 that can
connect to either OLDI TXes for the AM625 DSS, and not the VP2.
Alternatively, on some future TI SoCs, along with the above
configuration, the OLDI TX can _also_ connect to separate video sources,
making them work entirely independent of each other. In this case,
neither of the OLDIs are "companion" or "secondary" OLDIs, and nor do
they require one. They both are independent and primary OLDIs. The
following diagram represents such a configuration.
+-----+-----+ +-------+
| | | | |
| | VP1 +--+----------->+ OLDI0 | (Primary - may need companion)
| | | | | |
| +-----+ | +-------+
| | | |
| | VP2 | |
| | | |
| DSS +-----+ | +---+ +-------+
| | | +-->+ M | | |
| | VP3 +----->+ U +--->+ OLDI1 | (Companion or Primary)
| | | | X | | |
| +-----+ +---+ +-------+
| | |
| | VP4 |
| | |
+-----+-----+
Note that depending on the mux configuration, the OLDIs can either be
working together in tandem - sourced by VP1, OR, they could be working
independently sourced by VP1 and VP3 respectively.
The idea is to support all the configurations with this OLDI TX schema.
The OLDI functionality is further supported by a system-control module,
which contains a few registers to control OLDI IO power and other
electrical characteristics of the IO lanes.
Add devicetree binding schema for the OLDI TXes to support various
configurations, and extend their support to the AM625 DSS.
Signed-off-by: Aradhya Bhatia <a-bhatia1@ti.com>
Signed-off-by: Aradhya Bhatia <aradhya.bhatia@linux.dev>
Reviewed-by: "Rob Herring (Arm)" <robh@kernel.org>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://lore.kernel.org/r/20250528122544.817829-3-aradhya.bhatia@linux.dev
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>